Tricyclic antidepressants (TCA) overdosed?,”TCA overdose can cause hyperthermia as well as other anticholinergic effects, including dilated pupils and intestinal ileus. It can also cause seizures. TCA overdose decreases myocardial conduction velocity, leading to QRS prolongation and risk of ventricular arrhythmia. The major cause of mortality of TCA overdose is believed to be secondary to TCA-induced hypotension. In cases of hypotension, QRS prolongation, and ventricular arrhythmia, sodium bicarbonate is administered. Sodium bicarbonate improves systolic blood pressure
narrows the QRS complex and decreases the incidence of ventricular arrhythmia.”